Fast efficient resource distribution in long term evolution communication network scheduling

ABSTRACT

A method and system for determining, for a transmission time interval (TTI), an amount of resource units to be allocated to each cell served by at least one module in a wireless communication network are disclosed. The allocation is based on an estimated resource consumption of each cell, a resource limit of each cell and resource limits of the at least one module. For each TTI, a prioritized list of queues having information to be transmitted is determined, where each queue belongs to a cell of the plurality of cells. Also, for each TTI, in an order of priority of the queues, a number of resource units to be consumed by a queue is determined based at least in part on a number of resource units required to empty the queue.

TECHNICAL FIELD

The present invention relates to a method and system for schedulingresources in a wireless communication network.

BACKGROUND

In long term evolution (LTE) technology a scheduler is responsible forallocating both uplink (UL) and downlink (DL) resources to mobile userequipment (UE) every transmission time interval (TTI) of a radio frame.A TTI is 1 millisecond in duration. The complexity of scheduling andresource allocation combined with tight TTI constraints on processingprohibits recursive types of processing that would lead to optimalallocation of radio resources.

Resource scheduling may also be constrained based on licensingagreements, hardware constraints or software constraints. When finiteresources are available as a pool across a group of cells that are beingscheduled, a problem of how best to distribute these resources presentschallenges. Iterative solutions to achieve global optimization—that is,optimization of resource allocation over all cells—can find on optimaldistribution of resources. But these iterative solutions are too complexand time-consuming to be processed in a TTI.

Simplified pre-scheduling allocation of resources—that is, grossallocation of resources across the cells prior to detailed per userequipment (UE) or per-queue scheduling within each cell individually—canbe of relatively low complexity. However, if not done accurately, thesemethods will result in under-utilization of resources and possibly mayalso result in priority inversion of scheduling entities between cells.

SUMMARY

A method and system for pre-scheduling pooling of resource units of atleast one module in a node of a wireless communication network isprovided. The at least one module services a plurality of cells, andwhere each cell may have a plurality of queues. According to one aspect,the invention provides a method that includes determining, for atransmission time interval (TTI), a total amount of resource unitsavailable for allocation to the plurality of cells by the at least onemodule. An amount of resource units to be consumed by each of theplurality of cells is estimated based on resource limits for each of theplurality of cells and resource limits of the at least one module. Anamount of resource units to be allocated to each cell served by the atleast one module is determined based on the estimated resourceconsumption of each cell, the resource limits of each cell and theresource limits of the at least one module.

According to another aspect, an apparatus pre-schedules a total amountof resource units in a wireless communication network having a pluralityof cells. The apparatus includes a memory and a processor. The memory isconfigured to store a total amount of resource units available forallocation to the plurality of cells, an estimated amount of resourceunits to be consumed by each of the plurality of cells and an amount ofresource units allocated to each cell served by the at least one module.The processor is configured to determine, for a transmission timeinterval, the total amount of resource units available for allocation tothe plurality of cells by the at least one module. The process is alsoconfigured to estimate the amount of resource units to be consumed byeach of the plurality of cells based at least in part on resource limitsfor each of the plurality of cells and resource limits of the at leastone module. The processor is also configured to determine the amount ofresource units to be allocated to each cell served by the at least onemodule based on the estimated resource consumption of each cell, theresource limits of each cell and the resource limits of the at least onemodule.

According to still another aspect, a wireless communication systemincludes a network node having at least one module. The at least onemodule has a total number of allocable resource units. The at least onemodule is configured to allocate resource units to a queue of acorresponding cell served by the network node until the sooner of: (1)allocating resource units to the queue sufficient to empty the queue,(2) any of the resource units of the corresponding cell are exhausted,and (3) any of the resource units of the total allocable resource unitsis are exhausted.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is a block diagram of an exemplary wireless communication systemconstructed in accordance with principles of the present invention;

FIG. 2 is a flowchart of an exemplary process for pre-schedulingallocation of resource units in the context of the full schedulingprocess in accordance with principles of the present invention;

FIG. 3 is a flowchart of an exemplary process for pre-schedulingestimation of resource units in accordance with principles of thepresent invention;

FIG. 4 is a flowchart of an exemplary process for estimation of resourceunits for non-reserved queue resource allocation in accordance withprinciples of the present invention; and

FIG. 5 is a flowchart of an exemplary process for estimation of resourceunits for reserved queue resource allocation in accordance withprinciples of the present invention.

DETAILED DESCRIPTION

Before describing in detail exemplary embodiments that are in accordancewith the present invention, it is noted that the embodiments resideprimarily in combinations of apparatus components and processing stepsrelated to pre-scheduling resource allocation in a wirelesscommunication network. Accordingly, the system and method componentshave been represented where appropriate by conventional symbols in thedrawings, showing only those specific details that are pertinent tounderstanding the embodiments of the present invention so as not toobscure the disclosure with details that will be readily apparent tothose of ordinary skill in the art having the benefit of the descriptionherein.

As used herein, relational terms, such as “first” and “second,” “top”and “bottom,” and the like, may be used solely to distinguish one entityor element from another entity or element without necessarily requiringor implying any physical or logical relationship or order between suchentities or elements.

Referring now to the drawing figures, in which like referencedesignators denote like elements, there is shown in FIG. 1 an exemplarywireless communication system 100 constructed in accordance withprinciples of the present invention and having at least one base station102 serving a plurality of cells 104 a, 104 b and 104 c, hereinafterreferred to as cells 104. Each cell may serve a plurality of userequipment (UE) units in the coverage area of the cell.

The base station 102 has one or more modules 106, for example, modules106 a and 106 b. Each module 106 performs allocation of resource unitsamong one or more of cells 104, such as cells 104 a, 104 b and 104 c.The base station 102 is in communication with the cells 104 via one ormore antennas 120. As such, a module 106 includes a memory 108 and aprocessor 110. The processor 110 includes a pre-scheduler 112, whichincludes a resource estimator 114 and a resource allocator 116. Thepre-scheduler 112 estimates and allocates resource units prior toscheduling of the allocated resource units by individual schedulers 118a, 118 b and 118 c, referred to collectively as schedulers 118.

The resource allocator 116 implements a process to allocate resourcessuch as L2-bits, scheduling blocks (SB) (or physical resource blocks(PRB)) and scheduled entities, or may include any other finite scheduledresource such as an amount of processor cycles. The allocation ofresource units is based on an estimate, performed by resource estimator114, of a number of scheduling blocks (SB) needed to carry all data in aqueue for each of a plurality of queues. As such, the number of resourceunits required to empty a queue may depend upon channel conditions forthe user equipment (UE) associated with the queue. Any item that isscheduled may be referred to herein as a scheduling entity (SE), whichcan include, for example, a UE, a broadcast message, etc. Eachscheduling entity can have one or more queues. A number of schedulingblocks (SB) required to carry a certain amount of data can be estimatedbefore actual scheduling and link adaptation. Methods for estimatingscheduling block quantities are known and are beyond the scope of thisinvention.

Each queue is associated with a number of scheduling blocks (SB)required to empty the queue. The number of SBs required to empty a queuemay be estimated or reserved. For example, for broadcast messages, thenumber of SBs can be calculated accurately and are therefore reserved.As another example, for non-adaptive hybrid automatic repeat request(HARQ) re-transmissions, the number of required SBs is known and cantherefore be reserved. Differences between allocation of reserved queuesand unreserved queues are explained below with reference to FIGS. 4 and5.

The resource estimator 114 allocates resource units to queues in anorder of priority of the queues. The resource units estimated to beneeded to empty a queue of its data is compared to remaining unallocatedresource units. Queues are processed until a resource is exhausted. Theestimated resource utilization for each resource and each cell is thenemployed as a weighting function to pre-apportion a particular resourceto each cell as input to a detailed scheduling operation of a schedulerfor each cell. For example, if the estimated utilization of resourceunits for a particular cell is 20% then the weight function has a valueof 0.2 which is multiplied by the total resource units available toobtain the amount of resources allocated to the cell. After theallocation, the allocated resource units are checked against the cellresource limit and the smaller of the two will be used. If the totalallocated resource units across all cells is less than the availableresource units, the surplus resource units can be distributed to cellsthat can consume more resource units without exceeding the cell resourcelimit.

Accordingly, each cell 104 a, 104 b, 104 c has a respective scheduler118 a, 118 b, 118 c, associated therewith. More or fewer cells andschedulers may be implemented. The invention is thus not limited to thenumber of cells and schedulers shown in FIG. 1. In operation, eachscheduler 118 performs detailed scheduling of the resources allocated tothe cell. Upon completion of the detailed scheduling operation of ascheduler 118, any over-utilization or under-utilization of a finiteresource by the cells 104 can be accrued and applied as a surplus ordeficit when allocating resources for use in subsequent transmissiontime intervals (TTI). In other words, the total allocable resource unitsof a module for a present TTI may be based on a use of resource units ina previous TTI.

In performing the resource allocation, the resource estimator 114 useselastic factors that may be determined by simulation and field testing.Elastic factors are described below. As an example, a cell resource unitusage limit may be expressed as (100+f) %, where f is an elastic factorthat can be simulated to optimize or improve performance of a resourceallocation algorithm. The elastic factors are used in the initial phasesof resource allocation to accommodate estimation errors. At the laststep of resource allocation, the resource limits may be enforced.

Thus, some embodiments provide pre-scheduling pooling of resource units.The resource units may include processor cycles, frequency bandwidth,and other resource units. A total amount of resource units areassociated with a module 106 of a node or base station 102 of a wirelesscommunication network 100. A pre-scheduler 112 of the module 106determines, for each transmission time interval (TTI), an amount ofresources to be allocated to each of a plurality of cells 104. Theamount of resources allocated to a cell 104 is based on an estimatedresource consumption by the cell 104, the resource limits of the cell104 and the resource limits of the module 106. A prioritized list ofqueues having information to be transmitted is determined. In an orderof priority, the number of resource units allocated to a queue is basedat least in part on a number of resource units required to empty thequeue. For example, the number of resource units to be allocated by theresource allocator 116 to a queue may be based on whether the number ofresources to empty the queue of a cell exceeds the number of unallocatedresource units of the module or the number of unallocated resource unitsof the cell. When a number of resource units to empty a queue exceedsthe number of unallocated resources of the cell of the queue, but doesnot exceed the number of unallocated resource units of the module, theresource allocator 116 allocates the number of unallocated resourceunits of the cell to the queue. When the number of resource units toempty the queue exceeds the number of unallocated resource units of thecell, and exceeds the number of unallocated resource units of themodule, the smaller of the number of the unallocated resources of thecell and the number of unallocated resources of the module are allocatedto the queue. When the number of resource units to empty the queue isless than the number of unallocated resource units of the cell, and isless than the number of unallocated resource units of the module, thenumber of resource units to empty the queue are allocated to the queue.When the number of resource units to empty a queue of the cell exceedsthe number of unallocated resource units of the module, but does notexceed the number of unallocated resource units of the cell, the numberof unallocated resource units of the module are allocated to the queue.

Estimation of the amount of resources to be consumed by the queues ofthe cells may terminate upon occurrence of one of the followingconditions: (1) all queues are processed, (2) any resources of themodule are exhausted, and (3) any resources of all cells are exhausted.In the estimation phase of operation, some elastic factors are used toaccommodate estimation errors when considering resource allocation. Thefinal resource allocation is decided by normalizing the output of theresource estimator 114 against the actual resources available with allresource limits being enforced. Once the allocation of all resourceunits is determined, a main scheduling process in each cell is initiatedto schedule the resource units allocated to the cell. This scheduling isperformed by each cell during a transmission time interval in parallel.

FIG. 2 is a flowchart of an exemplary process performed by thepre-scheduler 112 for pre-schedule allocation of resource units inaccordance with principles of the present invention. The total amount ofresources that are available for pre-scheduling allocation is determinedfor a next transmission time interval (TTI) (step 122). A prioritizedlist of queues for the TTI is also determined (step 124) and is input tothe pre-scheduler 112. The resource estimation process is then performedaccording to a process A which is shown in FIG. 3 (step 126). Based onthe results of the resource estimation process A and cell resourcelimits, resource units are assigned to each cell (step 128). Then, inthe TTI, the schedulers 118 for the cells 104 shown in FIG. 1 performdetailed scheduling in parallel based on the resource units provided bythe base station 102 (steps 130 a, 130 b and 130 c).

The amount of resources actually consumed are compared to the resourcesavailable to determine an under-utilization or over-utilization ofresources (step 132). The determined utilization is fed back to step122, to adjust the total resources available for the next TTI.

The resource estimation process A of step 126 is described in detailwith reference to FIG. 3. The process begins at step S134 with the firstqueue in the prioritized list of queues determined in step 124 of FIG.2. The process determines the cell associated with the queue anddetermines whether the cell for this queue has resource units available(step 136). If the cell does not have resource units available, then adetermination is made whether all resources of the module or the cellsare exhausted (step 138). If all resources are exhausted, the processends.

If the cell for the present queue has available resources adetermination is made whether the queue is reserved (step 140). If thequeue is not reserved, then a non-reserved queue resource allocationprocess B is performed (step 142). Process B of step S130 is shown inFIG. 4. If the queue is reserved, then a reserved queue resourceallocation process C is performed (step 146). Process C of step 132 isshown in FIG. 5. After completion of process B or C, a determination ismade whether all resources are exhausted (step 138). If all resourcesare exhausted, then the process A of FIG. 3 ends. If not all resourcesare exhausted, a determination is made whether any queues are left (step148). If not, the process A ends. If one or more queues are left, thenthe process A continues with the next queue (step 150).

An exemplary process B of step 142 for non-reserved queue resourceallocation is described in detail in reference to FIG. 4. Uponcommencement of the process, a queue count is incremented (step 152). Adetermination is made as to whether sufficient resources are availablein this queue's cell but not within the module limit (step 154). If so,resource units are assigned for a portion of the queue up to the modulelimit (step S156). Otherwise, a determination is made as to whethersufficient resources are available in the module but not within the cell(step 158). If so, resource units are assigned for a portion of thequeue up to the cell limit, and the cell is marked as having noremaining resources (step 160). Otherwise, a determination is made as towhether sufficient resources are not available in this queue's cell orin the module (step 162). If sufficient resources are not available inthis queue's cell or in the module, then resource units are assigned fora portion of the queue up to the module or cell limit, whichever limitis smaller, and the module or cell, respectively, is marked as having noremaining resources available (step 164). Otherwise, a portion of theavailable resources are assigned to empty the queue (step 166). Then theamount of resources allocated for the cell and the module areincremented (step 168). The process then returns to step 138 of FIG. 3.

An exemplary process C of step 146 for reserved queue resourceallocation is described in detail in reference to FIG. 5. Adetermination is made as to whether a queue will fit within availableresources of the cell and the module (step 170). If not, the process Cends and control is returned to step 138 of FIG. 3. Otherwise, if thecurrent scheduling entity (e.g., a user equipment (UE)) has not alreadybeen assigned, then the scheduling entity count is incremented (step172). The allocated resource unit count is incremented for the cell andthe module (step 174). If any cell resources are exhausted, then thecell is marked as having no more resources available (step 176). Thus,in some embodiments, resource units may be allocated to a reserved queueonly when enough resource units are available to empty the reservedqueue.

Before providing an exemplary pseudo-code for pre-schedule resourceallocation implemented by the prescheduler 112 of the processor 110,certain definitions are set forth below:

acceptanceFactorSbs: a parameter used to determine if a queue can beselected based on number of remaining available SBs.

acceptanceFactorBits: a parameter used to determine if a queue can beselected based on number of remaining available bits.

availableBits: number of transfer block size (TBS) bits available(pooled). It is bitsBudgetTti minus the total number of reserved TBSbits for accepted queues.

availableSbs: number of available SBs (pooled). It is sbsBudgetTti minusthe total number of reserved SBs for accepted queues.

bandwidth[cellID]: the bandwidth in the unit of SBs for a cell.

bitsBudgetTti: the total number of TBS bits available for this TTI. Itcan be due to hardware limit, license limit, etc.

bitsPerSb[mcs]: the average number of bits that can be carried by a SBfor the given modulation and coding scheme (mcs).

cellSbsLimit: the cell SBs usage limit. It is a percentage and isrelative to the cell bandwidth. It may be set to more than 100% to allowestimation error. cellSbsLimit=1+f, where f is a conservative elasticfactor that can be simulated to optimize algorithm performance.

desiredSbsCell[cellId]: sum of desiredSbsQ[i] for the accepted(non-reserved) SEs in the cell.

desiredSbsQ[i]: the estimated number of non-reserved SBs needed for Qi(i-th queue in the combined sorted list).

minBits: the number of TBS bits limit. SE pooling is complete if thenumber of TBS bits available for SEs with reserved SBs is less than orequal to this limit.

modifiedDesiredSbsQ[i]: the estimated number of SBs that may be assignedto Qi taking into account pooling constraints.

modifiedQBits[i]: the estimated number of bits that may be assigned toQi taking into account pooling constraints.

pooledBitsLimit: the pooled data bits limit. It may be a percentage andis relative to the number of bits available. It is set to more (or less)than 100% to allow estimation error. pooledBitsLimit=1+g, where g is aconservative elastic factor that can be simulated to optimize algorithmperformance.

pooledSbsLimit: the pooled SBs usage limit. It is a percentage and isrelative to the absolute pooled SBs limit. It may be set to more (orless) than 100% to allow estimation error. pooledSbsLimit=1+e, where eis a conservative elastic factor that can be simulated to optimizealgorithm performance.

pooledSesLimit: the pooled limit on the number of SEs.

reservedSbsCell[cellId]: sum of reservedSbsQ[i] for SEs in the cell.

reservedSbsQ[i]: the number of SBs reserved for Qi.

sbsBudgetTti: the total number of SBs available for this TTI. It can bedue to hardware limit, license limit, etc.

sbStep: granularity of SBs in terms of SB allocation. The number ofallocated SBs has to be multiple of this number.

QBits [i]: amount of data for Qi. For a queue with reserved SBs, it isTBS bits. For a queue without reserved SBs, it is RLC SDU bits or RLCSDU bits plus certain number of bits to account for the header.

totalDesiredSbs: the accumulated amount of SBs requested to addressnon-reserved queues across all cells. For each TTI, the value isincremented from zero as each non-reserved queue is evaluated by thescheduler.

totalDesiredBits: the accumulated amount of RLC payload bits requestedto address non-reserved queues across all cells. For each TTO, the valueis incremented from zero as each non-reserved queue is evaluated by thepre-scheduler.

During execution of an algorithm for pre-schedule resource allocation,several constraints may be employed, such as the following:

(1) The number of pooled SEs is limited (selectedSes<=pooledSesLimit),where selectedSes is the number of selected scheduling entities.

(2) The pooled SB resource is limited. This constraint can be expressedas totalDesiredSbs/availableSbs<=pooledSbsLimit. It can also be writtenas availableSbs>=totalDesiredSbs/pooledSbsLimit (3) The cell SB resourceis limited. This constraint can be expressed asdesiredSbsCell[cellId]/(bandwidth[cellId]−reservedSbsCell[cellId])<=cellSbsLimit.It can also be written asbandwidth[cellId]>=reservedSbsCell[cellId]+desiredSbsCell[cellId]/cellSbsLimit

The pooled number of TBS bits is limited. It is expressed astotalDesiredBits/availableBits<pooledBitsLimit

An algorithm for pre-scheduling resource allocation performed by thepre-scheduler 112 of the processor 110 is outlined in pseudo code asfollows:

Begin algorithm;  Take the queue lists from all cells to be pooled andmake a new combined sorted (by priority) list;  Perform initializationfor all cells;  desiredSbsCell[cellId] = 0, reservedSbsCell[cellId] = 0,desiredBitsCell[cellId] = 0, reservedBitsCell[cellId] = 0, selectedSes =0, totalDesiredSbs = 0, totalDesiredBits = 0, currentCellUsage[cellId] =0, currentBbmUsage = 0, availableSbs = sbsBudgetTti, availableBits =bitsBudgetTti, pooledSbsUsage = 0  Initially, all cells to be pooledhave resources;  While (selectedSes < pooledSesLimit) & (pooledSbsUsage< pooledSbsLimit) & (totalDesiredBits / availableBits < pooledBitsLimit)& (SE pooling not complete);  Take the next queue (Qi) from the combinedqueue list;  Identify the SE and thus the cell it belongs to;  Obtainthe associated number of SBs, desiredSbsQ[i] or reservedSbsQ[i];  If thecell still has resources & SBs are not reserved for Qi;   Select thequeue;   If the SE to which the queue belongs is not selected;    Markthe SE as selected;    selectedSes += 1;   End;  sbsForPool = ceiling {(desiredSbsQ[i] + totalDesiredSbs) / pooledSbsLimit };  sbsForCell =ceiling { (desiredSbsQ[i] + desiredSbsCell[cellId]) / cellSbsLimit }; If { availableSbs < sbsForPool } & { bandwidth[cellId] >=reservedSbsCell[cellId] + sbsForCell };  modifiedDesiredSbsQ[i] =ceiling{ (availableSbs * pooledSbsLimit − totalDesiredSbs) / sbStep) } *sbStep;  modifiedQBits[i] = modifiedDesiredSbsQ[i] * bitsPerSb[mcs]; desiredSbsCell[cellId] += modifiedDesiredSbsQ[i]; desiredBitsCell[cellId] += modifiedQBits[i];  totalDesiredSbs +=modifiedDesiredSbsQ[i];  totalDesiredBits += modifiedQBits[i];  elseif {availableSbs >= sbsForPool } & { bandwidth[cellId] <reservedSbsCell[cellId] + sbsForCell };  modifiedDesiredSbsQ[i] =ceiling{ (bandwidth[cellId] − reservedSbsCell[cellId]) * cellSbsLimit -desiredSbsCell[cellId] } /sbStep} * sbStep;  modifiedQBits[i] =modifiedDesiredSbsQ[i] * bitsPerSb[mcs];  desiredSbsCell[cellId] +=modifiedDesiredSbsQ[i];  desiredBitsCell[cellId] += modifiedQBits[i]; totalDesiredSbs += modifiedDesiredSbsQ[i];  totalDesiredBits +=modifiedQBits[i];  Mark the cell with no more resources;  elseif {availableSbs < sbsForPool } & { bandwidth[cellId] <reservedSbsCell[cellId] + sbsForCell };  temp1 = ceiling{(availableSbs * pooledSbsLimit − totalDesiredSbs) / sbStep) } * sbStep; temp2 = ceiling{ { (bandwidth[cellId] − reservedSbsCell[cellId]) *cellSbsLimit - desiredSbsCell[cellId] } /sbStep} * sbStep; modifiedDesiredSbsQ[i] = min(temp1, temp2);  modifiedQBits[i] =modifiedDesiredSbsQ[i] * bitsPerSb[mcs];  desiredSbsCell[cellId] +=modifiedDesiredSbsQ[i];  desiredBitsCell[cellId] += modifiedQBits[i];  totalDesiredSbs += modifiedDesiredSbsQ[i];   totalDesiredBits +=modifiedQBits[i];   if temp1 >= temp2;    Mark the cell with no moreresources;   End;   If temp 1 <= temp2;    SE pooling is complete;  End;   Else;   desiredSbsCell[cellId] += desiredSbsQ[i];  desiredBitsCell[cellId] += QBits[i];    totalDesiredSbs +=desiredSbsQ[i];    totalDesiredBits += QBits[i];   End;   pooledSbsUsage= totalDesiredSbs / availableSbs;    elseif the cell still has resources(SBs are reserved for Qi);   sbsForCell = ceiling(desiredSbsCell[cellId]/ cellSbsLimit);     sbsForPool = ceiling(totalDesiredSbs /pooledSbsLimit);   If bandwidth[cellId] >= reservedSbsQ [i] +reservedSbsCell[cellId] + sbsForCell;   SbRoom = availableSbs −totalDesiredSbs / pooledSbsLimit;   If { (SbRoom >=acceptanceFactorSbs * reservedSbsQ[i] ) & (availableBits >=acceptanceFactorBits * QBits[i]) };    Select the queue;      If the SEto which the queue belongs is not selected;       Mark the SE asselected;       selectedSes += 1;      End;   reservedSbsCell[cellId] +=reservedSbsQ[i];   reservedBitsCell[cellId] += QBits[i];     availableSbs -= reservedSbsQ[i];      availableBits -= QBits[i];  pooledSbsUsage = totalDesiredSbs / availableSbs;   if availableSbs <=sbsForPool ∥ availableBits <= minBits;    SE pooling is complete;  Elseif bandwidth[cellId] = reservedSbsCell[cellId] + sbsForCell;   Mark the cell with no more resources;   End;      End;     End;  End;   If the last queue in the combined list is processed;    SEpooling is complete;   End;   End.

This ends the pre-schedule resource allocation algorithm. The number ofSEs to be processed by each cell level scheduler 118 can be simply thenumber of SEs selected so far for the cell. If the total number ofselected SEs is less than the module SE limit, one option is to assignthe next SE in the queue list as a resource to be processed by the cellscheduler and continue this process until the first of a) each cell hasreached its SE limit, or b) the module has reached its SE limit.

Exemplary steps for pooling of scheduling blocks (SB) are as follows:

allocatedSbsCell[cellId] = ceiling(availableSbs * desiredSbsCell[cellId]/ totalDesiredSbs) allocatedSbsCell[cellId] += reservedSbsCell[cellId]allocatedSbsCell[cellId] = min(bandwidth[cellId],allocatedSbsCell[cellId])${{if}\mspace{14mu} {sbsBudgetTti}} > {\sum\limits_{cells}{{allocatedSbsCell}\lbrack{cellID}\rbrack}}$The remaining SBs can be distributed to all cells for this TTI End

There are different distribution algorithms for distributing theremaining SBs as follows:

Equal split—which distributes the remaining SBs equally among allremaining queues;

Proportional to allocatedSbs[cellId]—which distributes the remaining SBsin proportion to the allocated SBs.

Proportional to (bandwidth[cellId]−allocatedSbs[cellId]); and

Proportional to number of SEs selected for the cell.

Exemplary steps for pooling of TBS bits is as follows:

allocatedBitsCell[cellId]=floor(availableBits*desiredBitsCell[cellId]/totalDesiredBits)

allocatedBitsCell[cellId]+=reservedBitsCell[cellId]

In the processes described above, queues are processed separately evenwhen multiple queues from the same scheduling entity (SE) are selected.More specifically, when multiple queues from the same SE are selected,the process adds the estimated number of scheduling blocks (SB) for allselected queues individually. Another option is to estimate the numberof SBs for the total amount of data of all queues of an SE. Thus, in oneembodiment, multiple queues belonging to a single user or a group ofusers can be combined into a single virtual queue when estimatingresource units required to empty all of the multiple queues. Thisalternative option may be expected to perform better, but at the cost ofadditional complexity.

In another alternative embodiment, if the SE limit is reached but theother resource limits are not reached, unselected queues of the selectedSEs can be processed in order of priority until one of the resourcelimits is reached. In yet another alternative embodiment, data bits forhybrid automatic repeat request (HARQ) re-transmissions may be excludedwhen considering data bit limits in the algorithm. In yet anotheralternative embodiment, a limit may be placed on queues per SE, or onthe total number of queues in the pool.

The processes presented herein provide a fast, low-complexity allocationof resources to each cell so that scheduling of the allocated resourcesat each cell can be performed in parallel without recursive computation.Thus, the processes presented herein result in more efficient use ofradio resources and pooled internal eNODE B resources without imposing acomputationally burdensome process on a scheduler of a cell. Thistranslates to higher throughput and capacity while enforcing licensingand other constraints.

The present invention can be realized in hardware, or a combination ofhardware and software. Any kind of computing system, or other apparatusadapted for carrying out the methods described herein, is suited toperform the functions described herein. A typical combination ofhardware and software could be a specialized computer system, having oneor more processing elements and a computer program stored on a storagemedium that, when loaded and executed, controls the computer system suchthat it carries out the methods described herein. The present inventioncan also be embedded in a computer program product, which comprises allthe features enabling the implementation of the methods describedherein, and which, when loaded in a computing system is able to carryout these methods. Storage medium refers to any volatile or non-volatilestorage device.

Computer program or application in the present context means anyexpression, in any language, code or notation, of a set of instructionsintended to cause a system having an information processing capabilityto perform a particular function either directly or after either or bothof the following a) conversion to another language, code or notation; b)reproduction in a different material form.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed herein above. In addition, unless mention was made above tothe contrary, it should be noted that all of the accompanying drawingsare not to scale. A variety of modifications and variations are possiblein light of the above teachings without departing from the scope andspirit of the invention, which is limited only by the following claims.

What is claimed is:
 1. A method of pre-scheduling pooling of resourceunits of at least one module in a node of a wireless communicationnetwork, the at least one module serving a plurality of cells, themethod comprising: determining, for a transmission time interval, atotal amount of resource units available for allocation to the pluralityof cells by the at least one module; estimating an amount of resourceunits to be consumed by each of the plurality of cells based at least inpart on resource limits for each of the plurality of cells and resourcelimits of the at least one module; and determining an amount of resourceunits to be allocated to each cell served by the at least one modulebased on the estimated resource consumption of each cell, the resourcelimits of each cell and the resource limits of the at least one module.2. The method of claim 1, further comprising: determining one of aresource surplus and a resource deficit after actual cell scheduling;and feeding back the one of the resource surplus and resource deficitfor determination of the total resource units available for the nexttransmission time interval.
 3. The method of claim 2, where the totalamount of resource units available for allocation in a TTI is based onone of (1) a hardware limitation of the at least one module, and (2) alicense limit plus the one of the resource surplus and resource deficit.4. The method of claim 1, wherein the amount of resource units to beconsumed by a cell served by the at least one module is estimated atleast in part from resources required to at least partially empty queuesselected to be transmitted from the corresponding cell.
 5. The method ofclaim 4, further comprising selecting a queue for a corresponding cellfor transmission based on at least in part the priority of the queuerelative to the priorities of the other queues served by the at leastone module.
 6. The method of claim 4, wherein the queues include atleast one reserved queue, and wherein a reserved queue for a cell isselected if the cell and the at least one module have enough resourceunits available to fully empty the queue.
 7. The method of claim 4,wherein the queues include at least one non-reserved queue, and whereinestimating resources to be consumed by a non-reserved queue includes:determining the resource consumption needed to empty the non-reservedqueue as completely as possible without exceeding the cell resourcelimits and the at least one module resource limits.
 8. The method ofclaim 1, further comprising: determining, for the transmission timeinterval, a prioritized list of queues having information to betransmitted, each queue belonging to a corresponding cell of theplurality of cells; and determining, for the transmission time interval,in an order of priority of the queues, a number of resources unitsestimated to be allocated to a queue based at least in part on a numberof resource units required to empty the queue.
 9. The method of claim 8,wherein a number of resource units to be allocated to a queue is basedat least in part on whether a number of resource units to empty a queueof a cell exceeds one of a number of unallocated resource units of theat least one module and a number of unallocated resource units of thecell.
 10. The method of claim 9, further comprising, when a number ofresource units to empty a non-reserved queue exceeds a number ofunallocated resource units of the cell, but does not exceed a number ofunallocated resource units of the at least one module, allocating thenumber of unallocated resource units of the cell to the queue.
 11. Themethod of claim 9, further comprising, when a number of resource unitsto empty the non-reserved queue exceeds a number of unallocated resourceunits of the cell, and exceeds a number of unallocated resource units ofthe at least one module, the smaller of the number of the unallocatedresources of the cell and the number of unallocated resources of the atleast one module are allocated to the queue.
 12. The method of claim 9,further comprising, when a number of resource units to empty thenon-reserved queue is less than a number of unallocated resource unitsof the cell, and is less than a number of unallocated resource units ofthe at least one module, the number of resource units to empty the queueare allocated to the queue.
 13. The method of claim 9, wherein when anumber of resource units to empty a non-reserved queue of the cellexceeds a number of unallocated resource units of the at least onemodule, but does not exceed a number of unallocated resource units ofthe cell, the number of unallocated resource units of the at least onemodule are allocated to the queue.
 14. The method of claim 9, whereintransmission resource allocation to a queue of a cell is based on apriority of the queue.
 15. The method of claim 9, wherein determining aprioritized list of queues further comprises identifying reservedqueues, and wherein transmission resource units are allocated to areserved queue only when enough resource units to empty the reservedqueue are available.
 16. The method of claim 9, wherein multiple queuesbelonging to a single user are combined as one virtual queue whenestimating the transmission resource units required to empty all queues.17. The method of claim 9, wherein the total allocable resource units ofthe at least one module in the present transmission time interval isbased at least in part on a use of resource units in a previoustransmission time interval.
 18. The method of claim 1, wherein theestimation of the amount of resource units to be allocated to the cellsterminates upon occurrence of one of the following conditions: allqueues are processed; any resources of the at least one module areexhausted; and any resources of all cells are exhausted.
 19. The methodof claim 1 further comprising: initially determining the number ofresource units allocated to the plurality of cells using elastic factorsto accommodate estimation errors; and normalizing the number of resourceunits allocated to the plurality of cells by enforcing cell resourcelimits and module resource limits.
 20. An apparatus for pre-scheduling atotal amount of resource units in a wireless communication networkhaving a plurality of cells, the apparatus comprising: a memory, thememory configured to store: a total amount of resource units availablefor allocation to the plurality of cells; an estimated amount ofresource units to be consumed by each of the plurality of cells; and anamount of resource units allocated to each cell served by the at leastone module; and a processor, the processor configured to: determine, fora transmission time interval, the total amount of resource unitsavailable for allocation to the plurality of cells by the at least onemodule; estimate the amount of resource units to be consumed by each ofthe plurality of cells based at least in part on resource limits foreach of the plurality of cells and resource limits of the at least onemodule; and determine the amount of resource units to be allocated toeach cell served by the at least one module based on the estimatedresource consumption of each cell, the resource limits of each cell andthe resource limits of the at least one module.
 21. The apparatus ofclaim 20, wherein each cell has at least one queue, and wherein theprocessor is further configured to allocate to each queue of acorresponding cell a number of resource units that will not exceed anumber of unallocated resource units of the cell.
 22. The apparatus ofclaim 20, wherein each cell has at least one queue, and wherein theprocessor is further configured to allocate to each queue of acorresponding cell a number of resource units that will not exceed anumber of unallocated resource units of the total amount of resourceunits.
 23. The apparatus of claim 20, wherein the processor is furtherconfigured to designate the cell as full when at least one type ofresource units of the cell have been fully allocated by the processor.24. A wireless communication system, comprising: a network node, thenetwork node having at least one module, the at least one module havinga corresponding total number of allocable resource units, the at leastone module configured to allocate resource units to a queue of acorresponding cell served by the network node until the sooner of:allocating resource units to the queue sufficient to empty the queue;any resource units of the corresponding cell are exhausted; and anyresource units of the total allocable resource units are exhausted. 25.The wireless communication system of claim 24, wherein a total ofallocable resource units per user equipment (UE) is based at least inpart on the channel conditions experienced by the UE.